Sam, the SEC Defensive Player of the Year from the University of Missouri, was selected in the seventh and final round of the draft two days ago by the St. Louis Rams. Sam has already signed an endorsement agreement with Visa Inc., which is also an NFL sponsor.

The only draft pick with higher jersey sales is former Heisman Trophy-winning quarterback Johnny Manziel, who was selected 48 hours earlier by the Cleveland Browns in the first round of the draft on May 8.

"If you look at the time, and the fact that he's already in the top five, that's instant clout," Weiss said in a telephone interview.

Rounding out the top five sellers are Houston Texans defensive end Jadeveon Clowney, who was the top pick, Minnesota Vikings quarterback Teddy Bridgewater, the final pick of the first round, and the Jacksonville Jaguars' Blake Bortles, the first quarterback selected at No. 3.

Fanatics Inc. said the top three rookie sellers are the same across its network of websites, which includes Fanatics.com and the online stores for the NFL, Browns and Rams.

Sales of jerseys at various price points are based on figures at NFLShop.com, the league's official online store, according to NFL spokesman Brian McCarthy. He wouldn't disclose specific sales figures.

Nike, which counts Brooklyn Nets forward Jason Collins, the first openly gay player in the four major U.S. sports as an endorser, is the NFL's official jersey supplier.

The buying power of the adult U.S. lesbian, gay, bisexual and transgender population was $830 billion last year, according to Bob Witeck, a gay-marketing strategist and corporate consultant.

The online store sold as many Manziel No. 2 jerseys throughout the draft as they sold Robert Griffin III, Andrew Luck and Tim Tebow jerseys during their respective drafts combined, McCarthy said.

Manziel has applied to trademark "Johnny Football," which is emblazoned on T-shirts also being sold at the NFL's official online store.

Weiss said he's evaluating endorsement offers to Sam, declining to give a timetable for his client to sign them. His jersey sales figures should convert any naysayers, Weiss said.

"There are people who are definitely skeptical what sort of tangible impact there would be in the marketplace," Weiss said. "This sort of answers that question. It's a finger to the wind test of what Mike's marketability looks like."

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